Glossary
Maysir
ميسرDefinition
Gambling — any transaction whose outcome depends on chance and where one party gains at another's pure loss.
Maysir is prohibited in Quran 5:90. The defining feature is a zero-sum bet with no underlying productive economic activity.
Contemporary scholars apply maysir to binary options, lottery-based products, highly leveraged retail trading where the probability of total loss is high, and most casino-style crypto protocols.